As I mentioned in another recent post, I was on a trip very recently that showed me some weaknesses in my kit. I have a 7D and 100-400, among other things.

There was some serious enthusiasts on the trip I was on, with kits in the $25k to $30k. I am not even considering going to that extreme, but I do need to make some decisions. they got some gorgeous pictures with 1DXs and 5D Mark IIIs, using 300 2.8, 400 2.8, as well as 500 4.0 and 600 4.0 (throw in some 1.4x and 2.0x to complete the picture).

I am reevaluating full frame sensors vs my 7D's 1.6 crop factor. As I shoot about 70% wildlife, I am loath to give up the extra reach of the 7D, but ISO above 1600 leaves something to be desired (I ended up shooting a lot at 2500 and 3200, and even some at 4000 and 5000 (threw most away though)). If I switch to full frame, then I would think I need to go with a 300 2.8 or 400 2.8 and a 1.4x and 2.0x teleconverters (500s and 600s are out of my price and weight range).

I would like to hear people's thoughts on these two lenses with and without teleconverters. Which is more important, the version of the lens or the version of the teleconverter used with it?

The lens would have to be used, and am prepared to be very patient waiting for a reasonable deal. Where would you recommend watching for sales of used lenses of this nature?

For full frame you need 1.6x squared pixellage since the crop factor is a linear (one-dimensional) measure. Thus you would need a full-frame with 45 MPx to crop down to 18 MPx with the same angle of view as the 7D.

If a 400 2.8 is in your budget, so is a 500 f4 as that lens is actually cheaper and better suited for wildlife imo. I would suggest looking in the buy and sell forum here in FM. Great deals can be had if you are patient. As far as your camera, I think a 7d is more suited to wildlife than a full frame camera because of the crop factor. Once you start cropping into a full frame image to 1.6 fov the noise advantage starts to level out anyway.

I would watch here, POTN, keh, bh.... Probably best bet would be here for good guys with good used stuff. About a month or two I averaged the asking prices for:
300 2.8 is ~ 3789 (34 last sold)
400 2.8 is ~ 5521 (14 last sold)

That's what you are looking at. A lot of wildlife guys love the 500. I would rent to see what might suit you best. Wait until some of the guys on here who actually own can advise you.

Personally, I am saving for a 400 to mix some sport work with occasional wildlife

300 2.8 and 500 or 600 f4 would be killer combinations.
I went 300 x.8 and 600 f4, just made the acqusition but I believe they are going to be most satisfactory.
These would go well with you 7d or better yet DIV or 1DX.

3iron wrote:
300 2.8 and 500 or 600 f4 would be killer combinations.
I went 300 x.8 and 600 f4, just made the acqusition but I believe they are going to be most satisfactory.
These would go well with you 7d or better yet DIV or 1DX.

Great advice. What do you think those combos would cost the OP?

EverLearning wrote:
There was some serious enthusiasts on the trip I was on, with kits in the $25k to $30k. I am not even considering going to that extreme,

Imagemaster, used is an option, but needing 1.3x1.3 more MP to get the same shot as the 7D is a negative. I would have to think a 7D Mark II will be coming out soon and should provide one to two stops additional ISO and push up the acceptable ISO by the same amount. That would solve a lot of my issues and still keep the reach that I love with the APS-C. A 400mm 2.8 with teles wouldn't hurt either, .

Something else that would have helped was the newest firmware upgrade for the 7D that would have made auto ISO much more usable. That would have done a better job of controlling IQ and allowed me to focus on the creative aspects of shooting.

EverLearning wrote:
Imagemaster, used is an option, but needing 1.3x1.3 more MP to get the same shot as the 7D is a negative. I would have to think a 7D Mark II will be coming out soon and should provide one to two stops additional ISO and push up the acceptable ISO by the same amount.
That may be a bit too optimistic... One stop or maybe two thirds of a stop improvement sound reasonable (that's what we've got in 5D III). I am afraid expecting two stops is wishful thinking.

jpeter, I would have loved to have shot at 1250. However, shooting wide open (f5.6 at 400mm) and at ISO 1600 often resulted in 1/250 or 1/320 of a second shutter speed. Under stable conditions that is low for a close moving object, but in a zodiac that is just too slow (even in quite calm waters). This is why I often had to shoot at 3200, or even 4000 ISO. If I needed 5000 or higher, I gave up and just enjoyed what I was seeing.

I found I was often shooting with minus EVs, especially for water-related action shots, as there was critical highlights in the agitated water. Perfect example was shooting breaches and bubble net feeding in small channels. The backdrop was normally dark rock and deep green trees, so -1 1/3 to -1 2/3 EV was needed to capture the details in the water.

I'm in a similar position and recently tested a 300mm 2.8 II + 2x TC III as well as a 500mm II on my 7D. I originally planned to go for the 300 2.8 + 2x TC to get a "cheap", handholdable 600mm for the 7D, but as PetKal pointed out, the AF of the 300 2.8 gets very slow when paired with the converter ... too slow for wildlife, it seems to me.

Fairtex, which 2x TC did you use? What type of wildlife do you normally shoot; BIF or slower moving mammals?

One of the guys on my trip was using a 5D M3 with the 300 and a 2x TC and was quite happy with it. He was also totally convinced that the 300 with 1.4x TC was rock solid. He seemed quite knowledgeable and got some beautiful shots with that combo. Did you try a 1.4x TC with it? Did you look at the 400 2.8 or even the 400 4.0?

EverLearning wrote:
I found I was often shooting with minus EVs, especially for water-related action shots, as there was critical highlights in the agitated water. Perfect example was shooting breaches and bubble net feeding in small channels. The backdrop was normally dark rock and deep green trees, so -1 1/3 to -1 2/3 EV was needed to capture the details in the water.

I used to do this as well. If you go by the LCD preview you get blinkies all over the water highlights, so you underexpose to protect them. I found though the rest of the shot was too noisy and that the LCD preview is very conservative being based on a tone mapped jpg that reflects your picture style. Most of the blinkies did not exist in the RAW image, it had 1 stop more headroom than the jpg. I now shoot at most at -1/3 - -2/3 unless it is very dark background and white subject. By careful PP in LR and PS I can bring out full detail in the water and still have good exposure on the background. I can highly recommend the Nik software Color EFEX plugin, especially the tonality tool. You can bring out a ton of extra detail in highlights. Also using the shadow/highlight tool on a layer and restricted to highlights is very effective.

The OP suggests he can afford the 400 2.8 but not the 500. Which versions of these lenses are being discussed? The 4002.8 IS and 500 f4 IS (both Mk I) are similarly priced when bought used and the 400 was more expensive new. Also the 400 f2.8 IS is VERY heavy so I'd say the 300 and 500 are the lenses most likely to meet cost and weight criteria.
You cant go far wrong with a crop camera, 500 + 1.4X IMO.